The invention relates to a rear light unit for a vehicle, especially for a passenger car, having a plurality of reflectors, and bulbs associated therewith, for providing a taillight, a brake light and a rear fog light, and optionally having bulbs for additional lamps, and a circuit for operating the rear light unit.
Vehicles currently have rear light units in which a plurality of reflectors and bulbs associated therewith, are combined in what is known as a multiple chamber light, wherein a separate chamber with a reflector is formed for each signal light. The reflectors are associated with individual sections of a lens plate which covers this multiple chamber light and is set into an opening of the car body and is mounted flush therewith. Arranged ahead of the lens plate sections for the taillight, brake light and rear fog light is a specially designed optical plate, having adjacent, horizontally oriented cylinder lenses that collect the light emitted by the bulb and incident parallel upon them and provide for adequate vertical dispersion. A rear light unit of this nature is described in EP 0,422,095 A2.
Due to the large number of chambers equipped with reflectors that are to be accommodated, and the minimum separation required in some countries between the brake light and the rear fog light, the rear light unit may occupy a commensurately large area on the rear of the vehicle, which can be perceived as visually unattractive, depending on the size of the vehicle.
It is the object of the invention to create a rear light unit which, with the same number of signal lights, improves the design options and permits a compact arrangement, and also a circuit for operating the same.
According to the invention a rear light unit is composed of at least four reflectors and bulbs, at least two of the bulbs having two levels of illumination. The high output level of one bulb provides a brake light and the high output level of the other provides a rear fog light. The two reflectors having two level bulbs are arranged apart at a spacing that corresponds to at least the minimum spacing required between the brake light and rear fog light. A number of reflectors serve multiple roles in this way, resulting in new design options and also a compact arrangement of the lights. In this context, the reflectors for the taillight, brake light and rear fog light can be arranged as four lights in a row, forming two reflector pairs of which the two outermost reflectors are provided to form the brake light and the rear fog light and have bulbs with two output levels.
In a further embodiment, all reflectors are provided with bulbs with two output levels, and together operate as the brake light when the rear fog light, is not in use. When the rear fog light is in use, only one outer reflector is used to form the brake light, while the outer reflector at the opposite end of the row of reflectors acts as the fog light. Accordingly, the prescribed minimum separation between brake light and rear fog light is provided.
For the brake light and the rear fog light, dual filament lamps may be used to provide two output levels. When all reflectors forming the rear light are used simultaneously to form the brake light, all reflectors are equipped with dual filament lamps. Where only one end reflector is used, only the outermost reflectors need to have dual filament lamps.
To create an attractive appearance, the reflectors can be arranged in two pairs such that the back of the pairs of reflectors form a circular area in the plan view. The wall separating the reflectors is preferably a straight web, which can be formed off-center in the circular area, where the end reflectors forming the brake light and rear fog light are each larger than the other, inside reflectors with which they are respectively paired. The separating walls of the two reflector pairs are parallel and arranged with at least the required minimum separation between the brake light and the rear fog light.
In a preferred arrangement, the reflector pairs can be arranged so that they are spaced vertically one above another, with the separating walls oriented horizontally. The reflector for the back-up light is preferably arranged in the space between the reflector pairs, and the reflector for the turn signal can be arranged horizontally adjacent thereto, preferably on the outside. In each case, the rear light unit is curved towards the fender in such a way that the lights, especially the signal lights, can also be seen from the side.
A cylindrical dispersion lens may be associated with the central reflectors of the row of four reflectors, the reflector for the rear fog light, and the brake light. The lenses are preferably formed in the proper color.
In accordance with the invention a circuit is provided for operating a rear light unit having lamps adjacent four reflectors which form the taillight, the brake light and the rear fog light, wherein a bulb with two output levels is associated with each reflector and wherein the output levels are operated either individually or in combination. The circuit includes a brake light switch and a fog light switch having two positions. In a first position of the fog light switch, a first lamp corresponding to the rear fog light is switched on to a high illumination. The brake light switch is connected to provide power to a second lamp when activated. In a second position of the fog light switch, the high illumination of the first lamp is turned off and the brake light switch is connected to provide power to all four lamps when activated.
A diode may be provided for the connection between the brake light switch and the first rear light when the fog light switch is in the second position. A diode may also be provided between the brake light switch and the second rear light when the fog light switch is in the first position.
All of these circuit arrangements make it possible to operate the rear light unit in accordance with the invention, using simple circuitry, with the legally required minimum separation between the brake light and the rear fog light, in a compact arrangement with a variety of design options.
The invention is explained below on the basis of a rear light unit for a passenger car.